Safety device for elevators.



H. WATSON.

SAFETY DEVICE FOR ELEVATORS.

' APPLICATION FILED MAY 29,1908. 910,247. Patented Jan. 19. 1909.

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Witvwoou H. WATSON; SAFETY DEVICE FUR ELEVATORS.

QPPLICATION FILED MAY 29, 1908.

Patented Jan. 19. 1909.

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H. WATSON. SAFETY DEVICE FOR ELEVATORS. APPLICATION FILED MAE-29, 1908.

Patented Jan. 19. 1909.

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anon wA'rson-"or wAsii noToN, DISTRICT OF COLUMBIA.

SAFETY DEVICE FOR ELEVKTORS.

No. sita /J22;

1 Specification of Letters Patent.-

Patented Jan. 19,1969;

Application filed May 29, 1908, Serial No; 435,798.

'To all whom'tt may concern:

Be it kiiownthat I, HUGH Larson, :1 citi zenofthe United States of. America, resid ingatashingtoii, in .the District of Cohunhia, have invented certain new and useful liiiprovcineiits in Safety Devicesfor Eleva tors, of which the following is a specification, This invent on relates to elevators and the invention may he termed aH-safety attachincnt-;'for elevator doors in that it is de Igned to prevent the application-ofpower to. the hoisting mechanism until all of the doors are closed;

Anobj'ect'of this illiQIltiOIi is toprovide novel means which will effectually prevent movement of the elevator controller- (that is the hand rope, lever, '0r..other meansof operatin an elevator. "switch h draulicva'lve of" doors is open. M

A further object of the invention is to provide novel means for opening the doors of an elevator shaft one at a time by 'means or the like) so long as any one ofa series of mechanism for each door, which mechanism is made operative by devices on the car,

preferably requiring the manipiil'ation of the ar attendant.

"With the foregoing and other objects in view, the invention Consistsindhe'dctails of construction and in the arrangei'nent and Jlflblflftllfifl of parts to be hereinafter more fully set forth and claimed.

In describing'the invention in detail, reference will be, had to the accompanying drawings forming part of this specification wherein like characters denote correspond ing parts in the several views,.in which-- Figure 1, is a sectional viow of an elevator shaft, showing the car and the mechanism embodying the invention applied thereto.-

Fig. 2, is' a view in elevation of the door oper-' ating device coupled with a switch in a circuit ofan electrical motor for driving the door operating mechanism andanother switch for the circuit of the elevator con-" shaft (i, but the di'nmD, is loosely mounted;

anisin, but as this particular feature forms no part of the .The car is provided with 'aswitch-closing lever a, pivoted thereon, and said lever has an anti-friction roller a, engaging a IDOV:

able member-B, of. the switch, which member B,- is'adapted to make electrical contact with the member '6. Said members are connected by'links O. p vThedofoir a, of the elevator shaft has a flexible member a, connectedto it, which member'is run over pulleysci, and has its present invention, it will not; 'be-described in detail.v

to the motor of the elevator hoisting mech-1 end connected to admin on which his Wound to open the dooiz IA mot-0r E, is geared to-drive'a shaft F,

,vvhich preferably extends up the elevator shaft, and said shaft is designed to actuate each-0f the doorshifting devices, iit being understood that one door shifting device will be provided at each. floor of an elevator shaft. Each shifting device has a shaft G, suitably supported and connected bya gear g to the shaft F, ahd'as' the shaftiF, is rotated, motion is communicated to the shaft A disk H, is secured to rotate with the on said shaft G, and rotates therewith only when the electromagnetsd, which are mounted-on the drum are energized and the cores thereof contact with the disk H. The

coresof the magnets (Z, are so close to the disk H, that any movement. of the drum D,

longitudinally of the shaft G, is almost imperceptible. Disks I aiid J, are connected to rotate together and the disk I, is coupled to the .drum D, by the brackets .A contact 7c. VVheiithe magnets (Z,are energized and clutch the disk H, the several disksyabove disk K, is mounted on the shaft G, and is coupled to the disk J, by means of the pins mentioned are caused to rotate with the;

shaft,- and, as said disksjhave electrical contacts (to be "presently described) the move-- ment of .said disks makes and breaks the circuit to the motor E, and to the control of the elevator motor; Thedisk K, has a. contact ring K, and, a

segmental Contact is, on its face, said rings being in electrical contact [with each other,

' and the space between the ends of the seg mental contact 70, contains insulation". k Brushes L and L, engage the contact ring 'K, and segmental contact is, respectively,

and said brushes have binding posts land'l,

to which the conductors and N, areconnected. The conductor M, is secured to the stationary member I), of the switch and the.

ductors engaged by brushes i and j, and,

said brushes have binding posts'r? and j respectively. A conductor O, is Connected to the binding post j and to the stationary member I), of the switch heretofore described. The binding post i has a wire P, connected to it, and said wire P is connected to the motor E, and to the feed Wire Q.

The magnets cl, are connected in series with the conductors d and 65 leading from the disks I and J, respectively. The drum D, carries a switch blade R, to engage the contacts 1' and r, from which the conductors r and 9, lead to the control of the motor for the elevator.

The conductors S and S, connect the brushes of the motor with the contacts 8 and s, and said contacts are engaged by the switch blade 1%, when the drum is rotated in the direction of the arrow in Fig. 3. These parts are designed to short-circuit the motor E, and the relation of the parts is such that the switch blade makes electrical connection with the contacts 8 and 8, when the elevator door has moved a predetermined distance.

In operation, when the elevator car has reached a floor, the lever a, is moved to force the switch-member B, into contact with the member 6, circuit is established from the feed wire Q, through the brush z", to the magnets and to the brush j, and by the conductor 0, to the switch member 0, thus establishing, as stated, a circuit through the magnets for the purpose of energizing the magnetic clutch. Simultaneously therewith, a current is established through the motor E, by the feed wire Q, conductors N, M, switch I), B, and return wire 39. The circuit just described is continued during the rotation of the disk K, and while the brushes are in engagement With the ring K, and segmental contact h, but said circuit is broken when one brush engages the insulation between the ends of'the segmental contact k. A circuit having been established through the motor E, said motor will rotate the shaft F thus driving the shaft G, and with it, the drum D, since said drum is coupled by the magnetic clutch to the disk H. Initial movement of the drum dis engages the switch blade R, from the contacts r and 1",. and hence the circuit is broken to the control of the motor for operating' the elevator and said motor will not be electrically connected again until the blade R, is restored to the position illustrated in Fig. 1. The winding drum continues to rotate by power from the motor -E, un til theswitch blade R, engages the contacts's and s. The conductors S and S, short-circuit the motor and this short circuit acts as a brake which immediately overcomes the momentum of the motor and arrests it. By'reason of the mechanism just described, an elevator door is mechanically opened and said door is closed by the operator. As the door is closed, the flexible connection AT, is unwound from the drum D, thus rotating the drum on the shaft G, and with said drum the disk K, is rotated until the brushes L and L, are restored to con tact withthe members K and is, respective ly, thus reestablishing a circuit through the motor E, when the switch member B, is caused to contact With the member 6.

In applying a door-controlling device to hydraulic elevators, the hand rope U, is run over a sheave 'u, on a shaft T, and said shaft is provided with a friction brake in the form of a lever a, pivoted at t. The lever hasa weight V, adjustable on its end, and said lever also has a connection with a solenoid core IV, working in the solenoid to. In this application of the invention, the door-operating mechanism is the same as that. heretofore described, except that the drum Z, has the switch blade 2, engaging the contacts 3 and 4:, and when the drum is rotated to open the door, the circuit through the conductors 5 and 6, (which are connected in series with each door-operating motor for the purpose of causing an interruption of the current through the solenoid if any door of the elevator shaft is open) is interrupted. When the doors are closed the solenoid is energized and the brake is lifted, and hence the elevator may be operated,i but if any door is open or partially open so that the contact blade is out of engagement with. the contacts, the solenoid will be demagnetized and the weight on the brake will prevent operation of the-hand rope or controlling device of the elevator. In this form, the switch plate 2, engages the'contacts 9 and 10 to close circuit through the conductors 7 and 8 designed to short circuit the motor as previously explained.

I claim 1. In combination with the doorsof an elevator shaft, mechanism for moving each for door, electrically controlled means throwing the door operatlng means into and out of action, a motor connected to drlve all of the door operating mechanisms, means for controlling the electric current to the motor,

and means for short circuiting the motor when the circuit to the motor is broken.

2. In combination with the doors of an elevator shaft, a car mechanism for moving each door, an electric motor for driving the door operating mechanism, means for supplying current to the motor, means on the elevator car for controlling the currentto elevator shaft, a car movable with relation to the doors, means for operating the doors, a motor independent of the car moving motor for actuating the .door operating means, electrically controlled" devices for connecting the door operating meanswith the actuating means, means for controlling the current to the motor, means for breaking the circuit to the motor, and means for simultaneously short circuiting the motor.

4; In combination with the doors of an elevator shaft, a car, a winding drum for each door, a flexible connection betweeneach drum and the door tdbe operated by'the drum, means for transmitting power to the drums, electrically controlled meansfor intermittently connecting the drums to the power transmitting means, and electrically controlled means for arresting the movement of the power transmitting means.

5. In an elevator, a shaft,a,car, a series of doors, an independently operated device for moving each door, means for connecting each doorand its operating device, a motor independent of the car moving motor, means .for connecting the first mentioned motor to drive the door operating devices, means on the car for controlling the connection between the motor driven member and the door operating devices, and means for electrically braking the motor of the door operating devices.

6. In an elevator, a shaft, a car, a "series of doors, an independently operated device for movlng each door, means for connecting each door and its operating dev1ce,a motor for connecting the first mentioned motor to drive the door operating devices, means on the car for controlling the connect-ion between the motor driven member and the door operating devices, and means for short circuiting the motor.

In testimony whereof I affix my signature in the presence or" two witnesses this 27th day of May, 1908.

HUGH WATSON. Witnesses J. Ross CoLHoUN, .FRANK S. APPLEMAN 4o independent of the car moving motor, means 

